The sensor suite onboard can monitor a variety of atmospheric, electromagnetic, temperature and spatial values. Toss your old IR thermometer away, the Tricorder will give you that measurement and distance as well. You might as well dump the GPS as well since the Tricorder has you covered. You will need a bit of skill in assembling electronics and soldering to finish the project, along with roughly $500 but the instructions are very detailed and in the end ... you get a working Tricorder!

"The Science Tricorder Mark 2 prototype sensor board contains ten different sensing modalities, organized into three main categories: atmospheric sensors, electromagnetic sensors, and spatial sensors. Many of the sensors are similar to those used in the Science Tricorder Mark 1, where the differences are centrally in upgrading sensors to higher-resolution versions where possible. The prototype sensor board also includes an imaging sensor, in the form of a cell phone camera, that is untested. Sensor boards for the Mark 2 are designed to be self-contained, include separate microcontrollers for low-level sensor communication, and as such are more easily upgraded."